How do I convert A1 to A01 without converting A10 to A010? In R

Question

How do I do the reverse of this? How to convert "A01" to "A1" using R? How do I convert A1 to A01 without converting A10 to A010? In R Basically, I need to combine the first character with the last character or two maintaining a total string length of 3. "0" is added as intervening character if needed.

Answer 1

Absorbance$row <- substring(Absorbance$Well.Position, 1, 1)
Absorbance$column <- substring(Absorbance$Well.Position , 2, 3)
Absorbance$column <- str_pad(Absorbance$column, 2, side = "left", pad = "0")
Absorbance$position <- paste(Absorbance$row, Absorbance$column, sep = "")